diff options
Diffstat (limited to 'drivers/char/sysrq.c')
| -rw-r--r-- | drivers/char/sysrq.c | 55 |
1 files changed, 46 insertions, 9 deletions
diff --git a/drivers/char/sysrq.c b/drivers/char/sysrq.c index 5f49280779f..13935235e06 100644 --- a/drivers/char/sysrq.c +++ b/drivers/char/sysrq.c @@ -41,7 +41,34 @@ #include <asm/irq_regs.h> /* Whether we react on sysrq keys or just ignore them */ -int sysrq_enabled = 1; +int __read_mostly __sysrq_enabled = 1; + +static int __read_mostly sysrq_always_enabled; + +int sysrq_on(void) +{ + return __sysrq_enabled || sysrq_always_enabled; +} + +/* + * A value of 1 means 'all', other nonzero values are an op mask: + */ +static inline int sysrq_on_mask(int mask) +{ + return sysrq_always_enabled || __sysrq_enabled == 1 || + (__sysrq_enabled & mask); +} + +static int __init sysrq_always_enabled_setup(char *str) +{ + sysrq_always_enabled = 1; + printk(KERN_INFO "debug: sysrq always enabled.\n"); + + return 1; +} + +__setup("sysrq_always_enabled", sysrq_always_enabled_setup); + static void sysrq_handle_loglevel(int key, struct tty_struct *tty) { @@ -182,6 +209,18 @@ static struct sysrq_key_op sysrq_showstate_op = { .enable_mask = SYSRQ_ENABLE_DUMP, }; +static void sysrq_handle_showstate_blocked(int key, struct tty_struct *tty) +{ + show_state_filter(TASK_UNINTERRUPTIBLE); +} +static struct sysrq_key_op sysrq_showstate_blocked_op = { + .handler = sysrq_handle_showstate_blocked, + .help_msg = "showBlockedTasks", + .action_msg = "Show Blocked State", + .enable_mask = SYSRQ_ENABLE_DUMP, +}; + + static void sysrq_handle_showmem(int key, struct tty_struct *tty) { show_mem(); @@ -219,13 +258,13 @@ static struct sysrq_key_op sysrq_term_op = { .enable_mask = SYSRQ_ENABLE_SIGNAL, }; -static void moom_callback(void *ignored) +static void moom_callback(struct work_struct *ignored) { out_of_memory(&NODE_DATA(0)->node_zonelists[ZONE_NORMAL], GFP_KERNEL, 0); } -static DECLARE_WORK(moom_work, moom_callback, NULL); +static DECLARE_WORK(moom_work, moom_callback); static void sysrq_handle_moom(int key, struct tty_struct *tty) { @@ -304,7 +343,7 @@ static struct sysrq_key_op *sysrq_key_table[36] = { /* May be assigned at init time by SMP VOYAGER */ NULL, /* v */ NULL, /* w */ - NULL, /* x */ + &sysrq_showstate_blocked_op, /* x */ NULL, /* y */ NULL /* z */ }; @@ -367,8 +406,7 @@ void __handle_sysrq(int key, struct tty_struct *tty, int check_mask) * Should we check for enabled operations (/proc/sysrq-trigger * should not) and is the invoked operation enabled? */ - if (!check_mask || sysrq_enabled == 1 || - (sysrq_enabled & op_p->enable_mask)) { + if (!check_mask || sysrq_on_mask(op_p->enable_mask)) { printk("%s\n", op_p->action_msg); console_loglevel = orig_log_level; op_p->handler(key, tty); @@ -402,9 +440,8 @@ void __handle_sysrq(int key, struct tty_struct *tty, int check_mask) */ void handle_sysrq(int key, struct tty_struct *tty) { - if (!sysrq_enabled) - return; - __handle_sysrq(key, tty, 1); + if (sysrq_on()) + __handle_sysrq(key, tty, 1); } EXPORT_SYMBOL(handle_sysrq); |